CVE-2022-43248 is a heap-buffer-overflow vulnerability identified in libde265 version 1.0.8, specifically within the function put_weighted_pred_avg_16_fallback located in fallback-motion.cc. Libde265 is an open-source H.265/HEVC video decoder library used to decode HEVC video streams. The vulnerability arises due to improper handling of memory buffers during weighted prediction averaging in the fallback motion compensation routine. An attacker can exploit this flaw by crafting a maliciously designed video file that triggers the heap-buffer-overflow condition when processed by the vulnerable library. This overflow can lead to a Denial of Service (DoS) by crashing the application or process utilizing libde265. According to the CVSS v3.1 vector (AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H), the vulnerability is remotely exploitable over the network without privileges but requires user interaction (e.g., opening or streaming the crafted video). The impact is limited to availability, with no direct confidentiality or integrity compromise indicated. No known exploits are currently reported in the wild, and no official patches or vendor advisories are linked, suggesting that mitigation may rely on updating libde265 to a fixed version once available or applying custom patches. The vulnerability is classified under CWE-787 (Out-of-bounds Write), a common memory corruption issue that can cause crashes or potentially be leveraged for further exploitation in some contexts, though no such escalation is documented here. Overall, this vulnerability affects any software or platform that integrates libde265 v1.0.8 for HEVC video decoding and processes untrusted video content.

For European organizations, the primary impact of CVE-2022-43248 is the potential for Denial of Service conditions in applications or services that utilize libde265 v1.0.8 to decode HEVC video streams. This could affect media players, streaming platforms, video conferencing tools, or any multimedia processing systems relying on this library. A successful exploit could disrupt business operations by crashing critical video processing components, leading to service outages or degraded user experience. While there is no direct data breach or integrity compromise, the availability impact can be significant for sectors dependent on video communications, such as media companies, broadcasters, telecommunications providers, and remote collaboration platforms. Additionally, embedded systems or IoT devices using libde265 for video decoding could be similarly affected, potentially impacting industrial or security camera systems. Given the requirement for user interaction (opening or streaming a malicious video), social engineering or phishing campaigns could be used to deliver the exploit payload. The absence of known exploits in the wild reduces immediate risk, but the medium severity score and ease of remote exploitation warrant proactive attention. Organizations should assess their software supply chain and multimedia processing stacks to identify use of libde265 v1.0.8 and plan for remediation to avoid service disruptions.

1. Inventory and Identify: Conduct a thorough inventory of all software products, platforms, and embedded systems that incorporate libde265, particularly version 1.0.8. This includes media players, streaming servers, video conferencing tools, and any custom applications processing HEVC video. 2. Update or Patch: Monitor the libde265 project and associated software vendors for patches or updated versions that address CVE-2022-43248. Apply updates promptly once available. If no official patch exists, consider applying community or vendor-provided workarounds or disabling fallback-motion.cc functionality if feasible. 3. Input Validation and Filtering: Implement strict validation and filtering of video content from untrusted sources. Employ sandboxing or isolated environments for processing untrusted video files to contain potential crashes. 4. User Awareness: Educate users about the risks of opening video files from unknown or untrusted sources to reduce the likelihood of triggering the vulnerability via social engineering. 5. Monitoring and Logging: Enhance monitoring of applications using libde265 for abnormal crashes or service interruptions that could indicate exploitation attempts. 6. Alternative Libraries: Where possible, evaluate replacing libde265 with alternative HEVC decoding libraries that are not affected by this vulnerability or have more active maintenance. 7. Network Controls: Use network-level controls to limit exposure to untrusted video streams, such as content filtering or proxying, especially in environments where video content is received from external sources. These targeted measures go beyond generic advice by focusing on the specific library, its usage contexts, and practical operational controls to reduce risk.